1. Technical Field
Example embodiments relate generally to a non-volatile memory device, and more particularly to a method of operating a non-volatile memory device to increase reliability.
2. Discussion of the Related Art
The individual memory cells in a non-volatile memory device, such as a flash memory device, may store data in accordance with a plurality of threshold voltage distributions, where each respective threshold voltage distribution is assigned to a corresponding logic state for stored data. In the non-volatile memory device, if, after a portion of blocks are programmed, read operations for the programmed blocks are repeatedly performed, a threshold voltage distribution of other blocks in an erased state may be undesirably shifted or broadened due to a read disturbance or a threshold voltage distribution of blocks adjacent to the programmed block may be undesirably shifted or broadened due to the read disturbance.
A non-volatile memory device using an on-chip buffered programming (OBP) method includes buffer memory cells including a single-level cell (SLC), which stores a data bit, and main memory cells including a multi-level cell (MLC), which stores two data bits, or a triple-level cell (TLC), which stores three data bits. The OBP method stores input data in the buffer memory cells, and transfers the stored data of the buffer memory cells to the normal memory cells. In this case, reliability of the buffer memory cells may be decreased by read disturbances due to a lot of data input/output commands on the buffer memory cells.